The effect of intensified nonverbal facilitation of swallowing on dysphagia after severe acquired brain injury: A randomised controlled pilot study.

BACKGROUND: There is little high-level evidence for the effect of the nonverbal facilitation of swallowing on swallowing ability in the subacute stage of rehabilitation following severe acquired brain injury (ABI). OBJECTIVE: To pilot test a randomised controlled trial to determine the effect of an intensification of the nonverbal facilitation of swallowing on dysphagia. METHODS: Ten patients with severe ABI and dysphagia were randomised into two groups at a highly specialised neurorehabilitation clinic.The intervention group received an intensification of the nonverbal facilitation of swallowing and the control group received basic care of the face and mouth in addition to treatment as usual for two sessions of 20 minutes per day for three weeks.Outcomes were Functional Oral Intake Scale (FOIS), Penetration Aspiration Scale (PAS), and electrophysiological swallowing specific parameters (EMBI). RESULTS: The intensified intervention was feasible. PAS and FOIS scores improved in both groups, with no differences between groups. The swallowing specific parameters reflected clinically observed changes in swallowing. CONCLUSIONS: PAS and FOIS are feasible instruments to measure dysphagia. It is possible and valid to measure swallowing frequency and kinematics using electromyography and bioimpedance. The definitive study should have widened inclusion criteria and optimise intervention timing to maintain patient arousal.

Structural brain maturation differs between preterm and term piglets, whereas brain activity does not.

AIM: The aim of the study was to investigate whether amplitude-integrated electroencephalography (aEEG) and cerebral magnetic resonance imaging (MRI) in preterm piglets would provide measures of cerebral functional, microstructural and anatomical maturation, which might reflect the signs of functional brain immaturity, documented in preterm piglets. METHODS: During July-October 2013 at the NEOMUNE Centre, Copenhagen University, Denmark, 31 preterm (90% gestation) and 10 term piglets underwent aEEG on days 1, 2, 4 and 11, and MRI on day 25. Physical activity levels were recorded. RESULTS: Preterm showed delayed neonatal arousal and physical activity, relative to term piglets. Preterm piglets had lower growth rates and brain volume than term piglets, but aEEG patterns were similar. MRI mean diffusivity was also similar, but fractional anisotropy (FA) was lower in preterm piglets (p < 0.001). CONCLUSION: Functional brain maturation, as assessed by aEEG, was relatively advanced in preterm piglets. Conversely, the low FA in the preterm piglets suggests that the white matter microstructure remains less mature in preterm compared to term piglets at postnatal day 25. The results might be utilised to define whether and how preterm piglets may contribute to preclinical models for brain development in preterm infants.

Cross-reactivity between methylisothiazolinone, octylisothiazolinone and benzisothiazolinone using a modified local lymph node assay.

BACKGROUND: In the light of the exceptionally high rates of contact allergy to the preservative methylisothiazolinone (MI), information about cross-reactivity between MI, octylisothiazolinone (OIT) and benzisothiazolinone (BIT) is needed. OBJECTIVES: To study cross-reactivity between MI and OIT, and between MI and BIT. METHODS: Immune responses to MI, OIT and BIT were studied in vehicle and MI-sensitized female CBA mice by a modified local lymph node assay. The inflammatory response was measured by ear thickness, cell proliferation of CD4+ and CD8+ T cells, and CD19+ B cells in the auricular draining lymph nodes. RESULTS: MI induced significant, strong, concentration-dependent immune responses in the draining lymph nodes following a sensitization phase of three consecutive days. Groups of MI-sensitized mice were challenged on day 23 with 0·4% MI, 0·7% OIT and 1·9% BIT - concentrations corresponding to their individual EC3 values. No statistically significant difference in proliferation of CD4+ and CD8+ T cells was observed between mice challenged with MI compared with mice challenged with BIT and OIT. CONCLUSIONS: The data indicate cross-reactivity between MI, OIT and BIT, when the potency of the chemical was taken into account in choice of challenge concentration. This means that MI-sensitized individuals may react to OIT and BIT if exposed to sufficient concentrations.

Epidermal filaggrin deficiency mediates increased systemic T-helper 17 immune response.

BACKGROUND: Cellular T-helper (Th)17 infiltrates dominate skin inflammation in filaggrin-deficient flaky tail (ft/ft) mice, and Th17 cells are found in both the skin and blood of patients with acute atopic dermatitis. However, the potential role of loss-of-function mutations in the filaggrin gene (FLG) for increased peripheral Th17 cells is unclear. OBJECTIVES: To study whether mutations in FLG influence the frequency of peripheral Th17 cells. METHODS: We studied blood samples from six adults with mutations in FLG and five controls without mutations for frequencies of cytokine-producing CD4(+) T cells. We evaluated ft/ft mice and wild-type (WT) control mice for interleukin (IL)-17-producing CD4(+) T cells in naive mice and following 2,4-dinitrofluorobenzene (DNFB) challenge. In addition, the T-cell receptor (TCR) Vß-chain repertoire was analysed by flow cytometry. RESULTS: Human studies showed increased frequency of peripheral Th17 cells in FLG mutation carriers when compared with WT individuals. Mouse studies showed increased frequency of peripheral Th17 cells in adult ft/ft mice but not in 2-week-old ft/ft mice. Moreover, altered TCR Vß-chain repertoire was found in ft/ft mice when compared with WT mice. An increased frequency of CD4(+) Vß10(+) T cells producing IL-17 was found in the spleen of adult ft/ft mice when compared with WT mice. Finally, DNFB challenge induced an increased number of Th17 cells in ft/ft mice compared with WT mice. CONCLUSIONS: Deficiency of filaggrin appeared to be a driver of increased peripheral levels of Th17 cells. This increase must be acquired as peripheral Th17 cells were found in adult ft/ft mice but not in 2-week-old ft/ft mice indicating involvement of exogenous factors.

Central common drive to antagonistic ankle muscles in relation to short-term cocontraction training in nondancers and professional ballet dancers.

Optimization of cocontraction of antagonistic muscles around the ankle joint has been shown to involve plastic changes in spinal and cortical neural circuitries. Such changes may explain the ability of elite ballet dancers to maintain a steady balance during various ballet postures. Here we investigated whether short-term cocontraction training in ballet dancers and nondancers leads to changes in the coupling between antagonistic ankle motor units. Eleven ballet dancers and 10 nondancers were recruited for the study. Prior to training, ballet dancers and nondancers showed an equal amount of coherence in the 15- to 35-Hz frequency band and short-term synchronization between antagonistic tibialis anterior and soleus motor units. The ballet dancers tended to be better at maintaining a stable cocontraction of the antagonistic muscles, but this difference was not significant (P = 0.09). Following 27 min of cocontraction training, the nondancers improved their performance significantly, whereas no significant improvement was observed for the ballet dancers. The nondancers showed a significant increase in 15- to 35-Hz coherence following the training, whereas the ballet dancers did not show a significant change. A group of control subjects (n = 4), who performed cocontraction of the antagonistic muscles for an equal amount of time, but without any requirement to improve their performance, showed no change in coherence. We suggest that improved ability to maintain a stable cocontraction around the ankle joint is accompanied by short-term plastic changes in the neural drive to the involved muscles, but that such changes are not necessary for maintained high-level performance.

The motor cortex drives the muscles during walking in human subjects.

Indirect evidence that the motor cortex and the corticospinal tract contribute to the control of walking in human subjects has been provided in previous studies. In the present study we used coherence analysis of the coupling between EEG and EMG from active leg muscles during human walking to address if activity arising in the motor cortex contributes to the muscle activity during gait. Nine healthy human subjects walked on a treadmill at a speed of 3.5­4 km h(-1). Seven of the subjects in addition walked at a speed of 1 km h(-1). Significant coupling between EEG recordings over the leg motor area and EMG from the anterior tibial muscle was found in the frequency band 24­40 Hz prior to heel strike during the swing phase of walking. This signifies that rhythmic cortical activity in the 24­40 Hz frequency band is transmitted via the corticospinal tract to the active muscles during walking. These findings demonstrate that the motor cortex and corticospinal tract contribute directly to the muscle activity observed in steady-state treadmill walking.

[Depression, stress and brain function]. / Depression, stress og hjernefunktion.

Many patients with major depression have elevated serum cortisol, which cannot be suppressed with dexamethasone. This points to a disturbance in the hypothalamus-pituitary-adrenal (HPA) axis, which might have pathogenetic importance. Recent investigations with MRI have shown an increased frequency of generalised, as well as localised atrophy in the brains of depressed patients. The reduced volume of the hippocampus is particularly interesting, because of the participation of this structure in the regulation of the individual's stress response. Furthermore, the hippocampus is of major importance for cognitive processes. There is evidence that the increased cortisol concentration is neurotoxic and may cause atrophy, as is known from Cushing's disease. This is supported by studies of the accumulated duration of depressive episodes, and also by the fact that drugs that dampen the HPA axis have proved to have antidepressant properties in clinical controlled, double-blind studies. This points to new principles in the treatment of major depression and underlines the importance of early intervention in order to prevent cerebral atrophy, which is probably reversible at the beginning of the disease process.

Segmental portal hypertension.

Isolated obstruction of the splenic vein leads to segmental portal hypertension, which is a rare form of extrahepatic portal hypertension, but it is important to diagnose, since it can be cured by splenectomy. In a review of the English literature, 209 patients with isolated splenic vein obstruction were found. Pancreatitis caused 65% of the cases and pancreatic neoplasms 18%, whereas the rest was caused by various other diseases. Seventy-two per cent of the patients bled from gastroesophageal varices, and most often the bleeding came from isolated gastric varices. The spleen was enlarged in 71% of the patients. A correct diagnosis in connection with the first episode of bleeding was made in only 49%; 22% were operated on because of gastrointestinal bleeding, but the cause of bleeding was not found. The diagnosis should be suspected in patients with gastroesophageal varices, but without signs of a liver disease, especially if isolated gastric varices are found. The diagnosis is confirmed by portography.

Variceal bleeding caused by segmental portal hypertension in association with situs inversus and malrotation.

An 18-year-old, previously healthy, woman was admitted to hospital because of haematemesis. Endoscopy showed large varices in the fundus of the stomach. Further investigations revealed segmental portal hypertension caused by situs inversus of the spleen. The case illustrates the importance of considering causes other than liver diseases in variceal bleeding.